#include <iostream>
#include <stdio.h>
#include <algorithm>
#include <cmath>
using namespace std;
struct node {
	double x,y;
};
node a[5003];
int cnt[5003];
int main() {
	int n;
//	freopen("in.txt", "r", stdin);
	while (cin>>n) {
		for (int i=0; i<n; ++i) {
			scanf("%lf%lf", &a[i].x, &a[i].y);
			cnt[i]=0;
		}
		for (int i=0; i<n; ++i) {
			for (int j=0; j<n; ++j) {
				if (pow(a[i].x-a[j].x,2)+pow(a[i].y-a[j].y,2)<16) ++cnt[j];
			}
		}
		int res=0;
		for (int i=0; i<n; ++i) if (cnt[i]>res) res=cnt[i];
		printf("%d\n", res+1);
	}
	return 0;
}
